The aim of this research was to evaluate the repellent activity of three essential components (cineole, terpinen-4-ol, alpha-pinene) against 10-15 days-old (2nd or 3rd instar) nymphs of Blattella germanica L. and Supella longipalpa Fabricius with Y-tube olfactometer. When all essential oil components were compared on the basis of repellent activity against B. germanica nymphs, cineole was the most repellent component at all times and there was no statistical significant difference between terpinen-4-ol and alpha-pinene. The highest repellency (96.4%) for cineole was seen at 20th min. Cineole was also more statistically significant repellent than the other two components against S. longipalpa nymphs. As a result, all components showed repellent activity against both cockroach species and exhibited no significant time dependent repellent activities (P>0.05).